Eventually, having made your slow way through the Garden of the Fallen, the somewhat narcotic effects of the bittersweet funerary herbs having dulled your senses and slowed your steps, you enter a cool cave, with thin wisps of mist swirling through it, and seeming to settle into your clothes, the damp, still, air a welcome cure for your half-drugged state.
Looking about, now that your vision has adapted to the dim light, you seem to have walked into yet another tomb; there are bodies set in shallow pools throughout the room, or in the wall niches that feed them through swift, though thin, waterfalls, slowly, though faster than one might expect, having a layer of stone form over them, their decay slowed by the water's preservative properties.
Carefully advancing further into the caverns, you find that the next chamber is where the bodies are placed after having been removed from the water; on narrow stone platforms around the periphery of the chamber, with a few fashioned from massive, still living, grey-spotted white mushrooms set closer to the center, apparent statues rest, green-glowing lichens having been enticed to grow over them, as well as, in some cases, red-hued mushrooms with narrow, pointed, caps, giving off faint light of their own. From the ceiling, almost like the many-stranded bead curtains seen in the City of Bells, hang the mycelia of numerous purple-tinted mushrooms, with three-tiered heads, which are set upside-down on the roof, and also, as is everything in this place, it seems - including their mycelium, which emit a cold, but pleasant blue light - glowing.
Tending the fungi are more of the mirror-skinned people from the Garden of the Fallen; possibly their kind are simply the owners of this strange building, or perhaps their race has been assigned the caste of dealing with the dead. In either case, they seem to be reasonably expert at their tasks, carefully spreading fertilizer, of various types, where it is desired that a certain type of fungi grow, and carefully, patiently, scraping it away where another, or none, should be.